Claude Opus 4.5 vs Claude Opus 5.5
As of Oct 15, 2026, Claude Opus 4.5 leads Claude Opus 5.5 in 0 of 7 shared categories.
Claude Opus 4.5
It used to be. Was SOTA in Reasoning.
Claude Opus 5.5
Yes. SOTA in Reasoning (tied), Coding (tied), Coding › Agentic (tied), Coding › Web dev, Long context (tied), and Factuality (tied).
| Category | Claude Opus 4.5 | Claude Opus 5.5 |
|---|---|---|
| General LLM | #41 · #41 in General LLM Margin 21.808510638297875 LMArena leaderboard dataset · Oct 13, 2026 | #2 · Near-SOTA · General LLM Margin 1.0638297872340416 LMArena leaderboard dataset · Oct 13, 2026 |
| Reasoning | #30 · Was SOTA · Reasoning Margin 16.489361702127653 LMArena leaderboard dataset · Oct 13, 2026 | #1 · Co-SOTA · Reasoning Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Math | #16 · #16 in Math Margin 33.33333333333333 Epoch AI benchmarking hub · Nov 24, 2025 | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 |
| Science | #68 · #68 in Science Margin — Epoch AI benchmarking hub · Nov 24, 2025 | #31 · #31 in Science Margin — Epoch AI benchmarking hub · Sep 22, 2026 |
| Coding | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 | #1 · Co-SOTA · Coding Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 |
| Coding › Agentic | — | #1 · Co-SOTA · Coding › Agentic Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 |
| Coding › Web dev | #58 · Was SOTA · Coding › Web dev Margin 45.6 LMArena leaderboard dataset · Oct 13, 2026 | #1 · SOTA · Coding › Web dev Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Long context | #20 · Was SOTA · Long context Margin 10.63829787234043 LMArena leaderboard dataset · Oct 13, 2026 | #1 · Co-SOTA · Long context Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Vision | — | #4 · Near-SOTA · Vision Margin 13.15789473684211 Epoch AI benchmarking hub · Sep 22, 2026 |
| Factuality | #40 · #40 in Factuality Margin 23.837209302325576 LMArena leaderboard dataset · Oct 13, 2026 | #1 · Co-SOTA · Factuality Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Abstraction (ARC) | #49 · #49 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Nov 24, 2025 | #1 · #1 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Sep 22, 2026 |
Claude Opus 4.5: $10 per 1M blended tokens.
Claude Opus 5.5: $8.000000000000002 per 1M blended tokens.
Claude Opus 4.5: closed weights.
Claude Opus 5.5: closed weights.
General LLM: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in General LLM at #2 against #41.
Reasoning: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Reasoning at #1 against #30.
Science: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Science at #31 against #68.
Coding › Web dev: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Coding › Web dev at #1 against #58.
Long context: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Long context at #1 against #20.
Factuality: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Factuality at #1 against #40.
Abstraction (ARC): As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Abstraction (ARC) at #1 against #49.
Claude Opus 4.5 · Claude Opus 5.5
Claude Opus 4.5 or Claude Opus 5.5?
As of Oct 15, 2026, Claude Opus 4.5 leads Claude Opus 5.5 in 0 of 7 shared categories.
Claude Opus 4.5 or Claude Opus 5.5 for General LLM?
As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in General LLM at #2 against #41.
Claude Opus 4.5 or Claude Opus 5.5 for Reasoning?
As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Reasoning at #1 against #30.
Claude Opus 4.5 or Claude Opus 5.5 for Science?
As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Science at #31 against #68.